Effects of alkali catalysts on the formation of methoxy aromatics during the microwave pyrolysis of eucalyptuspulverulenta

Methoxy aromatic compounds are important chemical intermediates with wide applications in industry, agriculture, and medicine. In this study, the production of bio-oil rich in methoxy aromatic compounds via microwave pyrolysis of Eucalyptus pulverulenta (EP) branch was investigated in the temperature range of 300-500 ºC. The results showed that 400 °C was the optimum temperature to achieve the highest yield of bio-oil (28.4 wt.%), where the concentration of methoxy aromatics in the biooil reached to 70.4 area%. The addition of Na2CO3 and K2CO3 has led to increases in the bio-oil yields. During the microwave pyrolysis of EP, Na2CO3 and K2CO3 increased the selectivity of methoxy aromatics in the bio-oil, while NaOH showed a negative impact on the selectivity of methoxy aromatics. Based on the findings of the study, the reaction pathways of methoxy aromatic compound formation during pyrolysis were proposed.